That’s because the context is changed. The child has not been defined as a personal being in reference to itself but rather in reference to the mothers will, who has been killed. It is the mother who has the right to define whether or not she is carrying a baby or an unwanted fetus. If she decides that she wants to give birth to a person, then the fetus is protected through the mothers legal rights as a citizen; not its own. In this case, in the absence of the mothers will, it is simply assumed that she intended to take the development of the fetus to full term; and therefore it is defined as murder relative to that particular context.
As for common-sense, that is just an assertion on your part. You cannot provide any circular legal argument that can determine or make evident that a fetus has a personal soul with intrinsic objective moral value given by God. You cannot do this any-more than you could show that gay marriage is wrong or that intelligent design should be taught in science classes. The problem is not atheism, but the secularisation of the legal system, which is a direct and inevitable result of the split between Church and State - Religion and circular politics.
Its quite sad to me that you as a Christian would say that evangelism can come later!!
This is the problem with Christians in America; they have lost sight of what truly matters (evangelism) and you have instead turned religious concerns into a legal war that you cannot possibly win.
It is not self-evident that a fetus is a person in a legal context.
God will take care of those innocent unborn children.
